Hyponatremia in the Literature

A roundup of recently published articles on the assessment, diagnosis, and management of hyponatremia in a variety of patient populations and clinical settings.

Hyponatremia Associated with Increased Hospital Costs for Patients with Liver Disease

In “Hyponatremia-Associated Healthcare Burden Among US Patients Hospitalized for Cirrhosis,” published in Advances in Therapy, the authors looked at more than 10,000 adult hyponatremic patients with cirrhosis (and more than 10,000 matched non-hyponatremic adult patients with cirrhosis) and compared hospital resource utilization, cost, and 30-day hospital re-admission in an effort to evaluate the healthcare burden of hyponatremia among patients hospitalized for cirrhosis. They found that hospital length of stay (LOS), hospital cost, length of stay in the intensive care unit (ICU), and ICU cost were higher for the patients with hyponatremia. This group also had a higher 30-day readmission rate. Specifically, hyponatremia was associated with “a 29.5% increase in hospital LOS, a 26.6% increase in overall hospital cost, a 23.2% increase in ICU LOS, and a 28.6% increase in ICU cost.” They concluded that “Hyponatremia in patients with cirrhosis is a predictor of increased hospital resource use and 30-day hospital re-admission, and represents a potential target for intervention to reduce healthcare expenditures for patients hospitalized for cirrhosis.”

Greater Nurse Awareness of Hyponatremia Can Decrease Mortality and Morbidity in Heart Failure

Because hyponatremia is common in patients with heart failure, the cardiovascular and advanced practice nurses who provide care to these patients should “be able to detect signs and symptoms of hyponatremia and, even when patients are asymptomatic, initiate appropriate treatment promptly to prevent complications.” The authors of “Management of Hyponatremia in Heart Failure: Role of Tolvaptan,” published in Journal of Cardiovascular Nursing, reviewed the epidemiology, pathophysiology, and signs and symptoms of hyponatremia in heart failure, and identified several challenges involved in correctly assessing and managing the patient with hyponatremia. They also reviewed current and emerging treatment options for hyponatremia, addressing the benefits and limitations of each. They noted that tolvaptan “can be used in hypervolemic and euvolemic hyponatremic patients with heart failure to correct serum sodium level without negatively affecting renal function.” They concluded that “Improved nurse understanding of hyponatremia in patients with heart failure may promote nurse-initiated or nurse-facilitated detection and management, which could decrease mortality and morbidity.”

Even Mild Hyponatremia Is Associated with Increased Risk of Death

The authors of “Mild Hyponatremia Is Associated with an Increased Risk of Death in an Ambulatory Setting,” published in Kidney International, used data from the Dallas Heart Study, to determine the prevalence and determinants of hyponatremia and its impact on mortality. For the study, hyponatremia was defined as serum sodium <135&thinsp;mEq/l. The study cohort consisted of 3,551 patients (median age 43 years) who were followed for a median of 8.4 years. The prevalence of hyponatremia in this cohort was 6.9%. The authors reported that hyponatremia in this cohort was “significantly associated with age, black ethnicity, presence of cirrhosis or congestive heart failure, and use of selective serotonin reuptake inhibitors,” and was “significantly associated with mortality after adjustment for age, gender, ethnicity, diabetes, hypertension, dyslipidemia, smoking, alcohol use, renal function, plasma C-reactive protein, use of antiepileptic drugs and selective serotonin reuptake inhibitors, and history of congestive heart failure, cirrhosis, and cancer.” Based on these data, the authors concluded that hyponatremia “mild hyponatremia is associated with an increased risk of death in a young and ethnically diverse community population.”